Strap System for Head-Mounted Displays

ABSTRACT

A strap system for a head-mounted display is disclosed. The strap system includes a rigid segment and a latching subsystem coupled to the rigid segment. The rigid segment has opposite first and second sides. The rigid segment couples to the head-mounted display from the first side. The latching subsystem couples to the second side of the rigid segment. The latching subsystem includes a plate including a pair of slots to respectively receive a pair of posts protruding from a detachable audio system. The latching subsystem also includes a pair of latches to latch to grooves in the pair of posts. Each latch of the pair of latches includes an opening that overlaps a respective slot of the pair of slots. The opening receives a respective post of the pair of posts.

RELATED APPLICATIONS

This application claims priority to U.S. Provisional Patent ApplicationSer. No. 62/174,359, filed on Jun. 11, 2015, entitled “Strap System forHead-Mounted Displays,” the disclosure of which is incorporated hereinby reference in its entirety.

TECHNICAL FIELD

This application relates generally to wearable technology andvirtual-reality technology, including but not limited to a strap systemfor a head-mounted display.

BACKGROUND

Virtual-reality head-mounted displays have wide applications in variousfields, including engineering design, medical surgery practice, militarysimulated practice, and video gaming. For example, a user wears avirtual-reality head-mounted display integrated with audio headphoneswhile playing video games so that the user can have an interactiveexperience in an immersive virtual environment.

However, it may be difficult for a user to properly adjust andcomfortably wear the head-mounted displays and the integrated audiosystems using the existing technology, which may negatively affect theuser's experience.

SUMMARY

In accordance with some embodiments, a strap system for a head-mounteddisplay includes a rigid segment and a latching subsystem coupled to therigid segment. The rigid segment has opposite first and second sides.The rigid segment couples to the head-mounted display from the firstside. The latching subsystem couples to the second side of the rigidsegment. The latching subsystem includes a plate including a pair ofslots to respectively receive a pair of posts protruding from adetachable audio system. The latching subsystem also includes a pair oflatches to latch to grooves in the pair of posts. Each latch of the pairof latches includes an opening that overlaps a respective slot of thepair of slots. The opening receives a respective post of the pair ofposts.

In accordance with some embodiments, a head-mounted display systemincludes a head-mounted display, a strap system for mounting thehead-mounted display on the user's head, and a detachable audiosubsystem. The strap system includes a semi-rigid segment to conform toa portion of the user's head, and a rigid segment connected to thesemi-rigid segment. The rigid segment includes a first side to couple tothe head-mounted display and a second side opposite to the first side.The strap system also includes a latching subsystem coupled to thesecond side of the rigid segment. The detachable audio subsystemincludes a speaker and a coupling subsystem including a pair of posts tocouple to the latching subsystem. Each post of the pair of posts has agroove. The latching subsystem includes a plate including a pair ofslots to respectively receive the pair of posts, and a pair of latchesto latch to the grooves in the pair of posts. Each latch of the pair oflatches includes an opening that overlaps a respective slot of the pairof slots. The opening receives a respective post of the pair of posts.

In accordance with some embodiments, a latching system for coupling anaudio system to a head-mounted display includes a plate including a pairof slots to respectively receive a pair of posts protruding from theaudio system, and a pair of latches to latch to grooves in the pair ofposts. Each latch of the pair of latches includes an opening thatoverlaps a respective slot of the pair of slots. The opening receives arespective post of the pair of posts. Each latch of the pair of latchesincludes a pair of members and a serpentine spring. The pair of membersjoin at a first end and are unconnected at a second end to define theopening. The serpentine spring is coupled to the first end of the pairof members.

Various advantages of the present application are apparent in light ofthe descriptions below.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the various described embodiments,reference should be made to the Description of Embodiments below, inconjunction with the following drawings. Like reference numerals referto corresponding parts throughout the figures and description.

FIG. 1 is a perspective view of a head-mounted display system comprisinga head-mounted display, a strap system, and a detachable audio subsystemin accordance with some embodiments.

FIG. 2 is an exploded view illustrating components of a head-mounteddisplay system in accordance with some embodiments.

FIG. 3A is a perspective view of a strap system including a rigidsegment and a latching subsystem in accordance with some embodiments.

FIG. 3B is a side view of a detachable audio subsystem for ahead-mounted display system in accordance with some embodiments.

FIG. 3C is a side view of a latching subsystem coupled with a strapconnector in accordance with some embodiments.

FIG. 3D is a side view of a latching subsystem, a coupling subsystem,and a strap connector in accordance with some embodiments.

FIG. 3E is a perspective view of a latching subsystem to couple with acoupling subsystem in accordance with some embodiments.

FIGS. 4A-4B are top views of a latching subsystem and its components inaccordance with some embodiments.

FIG. 4C is a top view of a plate of a latching subsystem in accordancewith some embodiments.

FIG. 4D is a top view of a pair of latches of a latching subsystem inaccordance with some embodiments.

FIG. 4E is a side view of a plate of a latching subsystem in accordancewith some embodiments.

FIG. 4F is a top view of a plate coupled with a pair of latches of alatching subsystem in accordance with some embodiments.

FIG. 4G is a bottom view of a latching subsystem in accordance with someembodiments.

FIG. 4H is a perspective view of components of a latching subsystem inaccordance with some embodiments.

FIGS. 5A-5C are side views illustrating decoupling mechanisms between acoupling subsystem and a latching subsystem in accordance with someembodiments.

DESCRIPTION OF EMBODIMENTS

Reference will now be made to embodiments, examples of which areillustrated in the accompanying drawings. In the following description,numerous specific details are set forth in order to provide anunderstanding of the various described embodiments. However, it will beapparent to one of ordinary skill in the art that the various describedembodiments may be practiced without these specific details. In otherinstances, well-known systems, methods, procedures, components,circuits, and networks have not been described in detail so as not tounnecessarily obscure aspects of the embodiments.

It will also be understood that, although the terms first, second, etc.are, in some instances, used herein to describe various elements, theseelements should not be limited by these terms. These terms are used onlyto distinguish one element from another. For example, a first segmentcould be termed a second segment, and, similarly, a second segment couldbe termed a first segment, without departing from the scope of thevarious described embodiments. The first segment and the second segmentare both segments, but they are not the same segment.

The terminology used in the description of the various embodimentsdescribed herein is for the purpose of describing particular embodimentsonly and is not intended to be limiting. As used in the description ofthe various described embodiments and the appended claims, the singularforms “a,” “an,” and “the” are intended to include the plural forms aswell, unless the context clearly indicates otherwise. It will also beunderstood that the term “and/or” as used herein refers to andencompasses any and all possible combinations of one or more of theassociated listed items. It will be further understood that the terms“includes,” “including,” “comprises,” and/or “comprising,” when used inthis specification, specify the presence of stated features, integers,steps, operations, elements, and/or components, but do not preclude thepresence or addition of one or more other features, integers, steps,operations, elements, components, and/or groups thereof.

FIG. 1 is a perspective view of a head-mounted display system 100 inaccordance with some embodiments. In some embodiments, the head-mounteddisplay system 100 comprises a head-mounted display 110, a strap system120, and a detachable audio subsystem 200. Although not shown due to theperspective, the head-mounted system 100 may have two audio subsystemslocated on left and right sides to provide audio signals to the user'sleft and right ears. Each of the left and right audio subsystems may usesubstantially symmetric structures for coupling the speaker to acorresponding rigid segment of the strap system 120.

The strap system 120 is used for mounting the head-mounted display 110on a user's head. In the example of FIG. 1, the strap 120 comprises arigid segment 130, a semi-rigid segment 140, and a rigid segment 150that are coupled to each other to adjustably wrap around side and backportions of the user's head.

In some embodiments, the strap 120 comprises a single and continuoussemi-rigid segment 140 including two arc portions, and each arc portionis to extend from above a user's ears to below the user's occipital lobeto conform to a portion of the user's head. Alternatively, the strap 120may comprise two separate and symmetric semi-rigid segments eachincluding an arc portion.

In some embodiments, the rigid segments 130 and 150 are respectivelyconnected to the semi-rigid segment 140. The rigid segments 130 and 150are also respectively coupled to the head-mounted display 110 andpositioned on respective sides of the user's head to extend along thelateral dimension (e.g., the Z dimension in FIG. 1). The strap 120 mayfurther include flexible segments (not shown) that are stretchablewithin the rigid segments 130 and 150 respectively to adjust the strap120 in accordance with the user's head.

In some embodiments, the strap 120 comprises a back piece 160 coupledwith the semi-rigid segment 140 to rest against the back of the user'shead (e.g., around the user's occipital lobe).

In some embodiments, the strap 120 comprises a top strap 170 coupled tothe back piece 160 and the head-mounted display 110 to adjustablyconform to the top of the user's head when the user is wearing thehead-mounted display.

In some embodiments, various electrical connection mechanisms (e.g.,flat flexible circuits and/or electric cables) are used in thehead-mounted display system 100 to provide power management, signaltransmission, and/or other functionalities to the head-mounted display110 and the detachable audio subsystem 200. For example, thehead-mounted display 110 is integrated with the detachable audiosubsystem 200 using suitable electrical connection mechanisms to provideboth visual and audio virtual-reality experiences to the user.

Various embodiments of the strap system 120 and the head-mounted displaysystem 100 are described in U.S. patent application Ser. No. 14/603,335(Attorney Docket No. 010235-01-5016-US), filed on Jan. 22, 2015, andU.S. patent application Ser. No. 14/681,001 (Attorney Docket No.010235-01-5028-US), filed on Apr. 7, 2015, the disclosures of which areincorporated herein by reference in their entireties.

FIG. 2 is an exploded view illustrating components of the head-mounteddisplay system 100 in accordance with some embodiments. In someembodiments, the rigid segment 150 includes a side 151 opposite to aside 153 along the X dimension as shown in FIG. 2. The side 151 of therigid segment 150 couples to the corresponding side of the head-mounteddisplay 110 via a suitable coupling structure. For example, the rigidsegment 150 includes a cylindrical structure 152 with a hollow center toaccommodate a cylindrical structure 112 protruding from a side 114 ofthe head-mounted display 110. The cylindrical structure 152 furtherincludes grooves to fasten to the side 114 of the head-mounted display100. The detailed structure of the cylindrical structure 152 may besubstantially symmetrical to a cylindrical structure 132 of the rigidsegment 130 as shown in FIG. 2. The rigid segment 130 also includes flatcircuit 134 to couple to the head-mounted display 110. The side 153 ofthe rigid segment 150 is coupled to a latching subsystem 300.

FIG. 3A is a perspective view of the rigid segment 150 and the latchingsubsystem 300 in accordance with some embodiments. The latchingsubsystem 300 includes a plate 310, a pair of latches 320 and 340disposed over the plate 310, a base 360 underlying the plate 310, and acover 370 to cover serpentine springs of the pair of latches 320 and340. The structures of the respective components of the latchingsubsystem 300 are further discussed in details with reference to FIGS.4A-4H.

FIG. 3B is a side view of the detachable audio subsystem 200 for ahead-mounted display system in accordance with some embodiments. Thedetachable audio subsystem 200 comprises a speaker 210, an arm 220coupled to the speaker 210, a strap connector 230 coupled to the arm220, and a coupling subsystem 240 coupled to the strap connector 230.The coupling subsystem 240 is releasably coupled to the strap 120 (e.g.,the rigid segment 150) for the head-mounted display system 100 asillustrated in FIGS. 1-2.

The speaker 210 may be an on-ear headphone speaker, an around-earheadphone speaker, an over-ear headphone speaker, an in-ear headphonespeaker, an earbud speaker, or any other suitable style of speaker.

As shown in FIG. 3B, the strap connector 230 and the speaker 210 arecoupled to the arm 220 in respective portions distributed along thelength (e.g., the Y dimension) of the arm 220. The arm 220 may furthercomprise a four-bar linkage to provide inward and outward movement ofthe speaker with respect to the user's ear. Various embodiments of thefour-bar linkage and other possible structures of the arm 220 aredescribed in U.S. patent application Ser. No. 14/627,639 (AttorneyDocket No. 010235-01-5017-US), filed on Feb. 20, 2015, the disclosure ofwhich is incorporated herein by reference in its entirety.

The strap connector 230 includes a side 232 coupled to the arm 220 and aside 234 coupled to the coupling subsystem 240, and the side 232 and theside 234 are opposite to each other along the X dimension as illustratedin FIG. 3B. Various embodiments of the strap connector 230 are describedin U.S. patent application Ser. No. 14/627,639.

FIG. 3C is a side view of the latching subsystem 300 coupled with thestrap connector 230 via the coupling subsystem 240 in accordance withsome embodiments. The latching subsystem 300 includes a side 302 coupledto the coupling subsystem 240 and a side 304 to couple to the strap 120(e.g., the rigid segment 150 of FIGS. 1-2). The side 302 and the side304 are opposite to each other along the X dimension as illustrated inFIG. 3C.

In some embodiments, the latching subsystem 300 is a component of thestrap 120 (e.g., the rigid segment 150) that is fixedly connected to thestrap 120. Alternatively, the latching subsystem 300 is coupled to thestrap 120 using any suitable structure; once coupled, the latchingsubsystem 300 may be considered part of the strap 120.

FIG. 3D is a side view of the latching subsystem 300, the couplingsubsystem 240, and the strap connector 230 in accordance with someembodiments. The coupling subsystem 240 includes a base 242, one or moreposts 250 (e.g., a pair of posts) extending from the base 242 andthrough a spacer 246 to couple to the latching subsystem 300, and aspring 244 positioned between the base 242 and the spacer 246 to deform(e.g., to release from a compressed length to or toward a naturallength) to detach the coupling subsystem 240 from the latching subsystem300 when the posts 250 decouple from the latching subsystem 300.Opposite ends of the spring 244 contact the spacer 246 and the base 242.One or more coupling elements 260 (e.g., screws) are used to couple thecoupling subsystem 240 to the strap connector 230.

In some embodiments, the base 242 is a circular boss. The base 242includes a side 241 engaged with the side 234 of the strap connector 230and a side 243 opposite to the side 241. The posts 250 extend from theside 243 of the base 242 to insert into the latching subsystem 300.

In some embodiments, the spring 244 contacts the side 243 of the base240, to detach the detachable audio system 240 from the latchingsubsystem 300 when the pair of posts 250 decouple from the latchingsubsystem 300 (e.g., from a pair of latches as discussed in FIGS.4A-4H).

In some embodiments, each post 250 includes an end 251 inserted into arespective opening (not shown) in the base 242. Each post 250 alsoincludes an end 252 opposite to the end 251 to couple to the latchingsubsystem 300. The end 252 includes a tip 254 to be inserted into anopening of the latching subsystem 300. The end 252 also includes agroove 256 to engage with concave edges of a latch in the latchingsubsystem 300.

FIG. 3E is a perspective view of the latching subsystem 300 to couplewith the coupling subsystem 240 in accordance with some embodiments. Asshown in FIG. 3E, the pair of posts 250 insert into respective openingsof the pair of latches 320 and 340 to couple the coupling subsystem 240to the latching subsystem 300. The concave edges of the latches 320 and340 respectively latch to the grooves of the pair of the posts 250.Various embodiments of the coupling subsystem 240 are described in U.S.Patent Application No. 62/174,298 (Attorney Docket No.010235-01-5031-PR), filed on Jun. 11, 2015, the disclosure of which isincorporated herein by reference in its entirety.

FIGS. 4A-4H are views of the latching subsystem 300 from differentangles in accordance with some embodiments. As illustrated in FIGS. 4Cand 4E, the plate 310 includes a pair of slots 312 and 313 torespectively receive the pair of posts 250 protruding from thedetachable audio system 200 (e.g., the coupling subsystem 240). Theplate 310 also includes a protrusion 314 protruding from the top surfaceof the plate 310 to be used for coupling the plate 310 with the pair oflatches 320 and 340. The plate 310 further include a pair of protrusions317 and 318 separate from the protrusion 314 and located next to theends of the slots 312 and 313 as shown in FIGS. 4C-4D. The protrusions317 and 318 respectively correspond to end portions 393 and 394 ofapertures 395 and 396, and the apertures 395 and 396 are connected tothe openings 342 and 322 respectively. When the pair of latches 320 and340 are coupled to the plate 310 as shown in FIG. 4F, the protrusions317 and 318 respectively extend through the end portions 393 and 394 onthe latches 340 and 320, and the protrusion 314 extends through theaperture 347 of the latch 340 and the aperture 327 of the latch 320 todefine the positions of the latches 320 and 340 relative to the plate310 as shown in FIG. 4F. The apertures 395 and 396 overlap the slots 312and 313 on the plate 310 respectively. As illustrated in FIGS. 4E and4G, a projection 316 protrudes from the back of the plate 310 to coupleto a slot on the base 360.

In some embodiments, the latch 320 is identical to the latch 340 or amirror image of the latch 340. The latch 340 includes a pair of members344 joined at an end 343 and unconnected at an end 345. The members 344define an opening 342 to receive the post 250. For example as shown inFIG. 4D, each member 344 of the pair of members includes a concave edgeportion 351 and the concave edge portions 351 face each other to definethe opening 342.

Similarly, the latch 320 includes a pair of members 324 joined at an end323 and unconnected at an end 325. The members 324 define an opening 322to receive the post 250. For example as shown in FIG. 4D, each member324 of the pair of members includes a concave edge portion 331 and theconcave edge portions 331 face each other to define the opening 322.

In some embodiments, the openings 342 and 322 narrow at a neck thatforms the end of the concave edge portions and then widen again (e.g.,to a width equal to or greater than the width of the slots 312 and 313).As shown in FIG. 4D, the widened portions extend to form the apertures395 and 396, and the end portions 393 and 394 of the apertures 395 and396 receive the protrusions 317 and 318 from the plate 310. In someembodiments, the width (e.g., maximum width) of the apertures 395 and396 are equal to or greater than the tips 254 of the posts 250.

In some embodiments, the latch 340 includes a serpentine spring 350coupled to the pair of members 344. For example, the serpentine spring350 is disposed next to the pair of members 344 such that at least aportion of the serpentine spring 350 is parallel to the length of thepair of members 344 as shown in FIG. 4D. Similarly, the latch 320 alsoincludes a serpentine spring 330 coupled to the pair of members 324 toadjust a size of the opening 322 when deformed. The serpentine spring330 may be disposed next to the pair of members 324 such that at least aportion of the serpentine spring 330 is parallel to the length of thepair of members 324.

In some embodiments when the latches 320 and 340 are in initial states(e.g., relaxed states), the widths of the openings 342 and 322 arerespectively narrower than the groove diameters of the posts 250. Whenthe tips 254 are inserted into corresponding openings 342 and 322, theopenings 342 and 322 widen to accept the posts 250 and the edges 351 and331 latch onto the grooves 256 of the pair of posts 250.

In some embodiments, the latch 340 includes a portion 346 coupledbetween the end 343 of the pair of members 344 and an end 352 of theserpentine spring 350. The portion 346 includes an aperture 347.Similarly, the latch 320 includes a portion 326 coupled between the end323 of the pair of members 324 and an end 332 of the serpentine spring330. The portion 326 includes an aperture 327.

In some embodiments, the latches 320 and 340 are disposed over the plate310 and coupled to the plate 310 such that the serpentine springs 330and 350 overlap each other. Additionally, the opening 342 of the latch340 overlaps the slot 312 of the plate 310, and the opening 322 of thelatch 320 overlaps the slot 313 of the plate 310.

In some embodiments, the base 360 is elongated. As shown in FIG. 3A, theplate 310 and the pair of latches 320 and 340 are coupled to the base360 over a surface 368 of the base 360. The rigid segment 150 is coupledto the base 360 over a surface 366 of the base 360 opposite to thesurface 368.

In some embodiments, the cover 370 is elongated. The cover 370 iscoupled to the base 360 and the pair of latches 320 and 340 to cover theoverlapped serpentine springs 330 and 350. The spacer 380 is locatedbetween the cover 370 and the pair of latches 320 and 340 to cover theoverlapped serpentine springs 330 and 350.

In some embodiments, the cover 370 includes a pair of projections 372and 376 opposite to each other as shown in FIG. 4B. The projection 372includes an aperture 374 and the projection 376 includes an aperture378.

In some embodiments as shown in FIG. 4D, the latch 340 further includesa portion 348 coupled to an end 354 of the serpentine spring 350opposite to the end 352. The portion 348 includes an aperture 349.Similarly, the latch 320 further includes a portion 328 coupled to anend 334 of the serpentine spring 330 opposite to the end 332. Theportion 328 includes an aperture 329.

As shown in FIG. 4B, the base 360 includes a pair of apertures 362 and363. A pair of connectors 391 and 392 (e.g., bolts, screws, fasteners),shown in FIG. 4G, are used to couple the cover 370, the pair of latches320 and 340, and the base 360 together. For example, from the bottomsurface of the base 360, the connector 391 inserts through the aperture362 of the base 360, the aperture 349 of the latch 340, and the aperture374 of the cover 370. The connector 392 inserts through the aperture 363of the base 360, the aperture 329 of the latch 320, and the aperture 378of the cover 370. In some embodiments, a pair of nuts 359 and 357respectively fasten the pair of connectors 391 and 392 from the topsurface of the base 360.

In some embodiments as shown in FIGS. 4B and 4G, the base 360 furtherincludes a slot 364 (e.g., an oval slot) and the base 360 is coupled tothe plate 310 by inserting the projection 316 of the plate 310 throughthe slot 364.

Referring to FIGS. 4C-4F and 3E, when the detachable audio subsystem 200are coupled to the strap 120, the tips 254 of a pair of posts 250protruding from the coupling structure 240 are inserted into theopenings 342 and 322. The posts 250 are forced into the openings 342 and322 to trigger widening of the members 344 and 324 until the concaveedges 351 and 331 latch to the grooves 256 of the posts 250. As themembers 344 and 324 widen, the portions 346 and 326 may pivot along theprotrusions 317 and 318 which extend through the apertures 347 and 327.The pivoting motions can be further transferred to the serpentinesprings 350 and 330 to deform the serpentine springs 350 and 330linearly along the Z dimension.

In order to decouple the detachable audio subsystem 200 from the strap120, the user can slide the detachable audio subsystem 200 along the Zdimension to slide the posts 250 from the openings 342 and 322 towardsthe wider apertures 395 and 396. As the audio subsystem 200 slides, thegrooves 256 of the posts 250 force the members 344 and 324 to widen.When the posts 250 slide into the apertures 395 and 396, because thewidth of the apertures 395 and 396 are equal to or greater than the tips254 of the posts 250, the posts 250 can be pulled out from the apertures395 and 396 freely to decouple the detachable audio subsystem 200 fromthe strap 120.

FIGS. 5A-5C are side views illustrating decoupling mechanisms betweenthe coupling subsystem 240 and the latching subsystem 300 in accordancewith some embodiments. When the user decouples the audio subsystem 200from the strap system 120, the posts 250 slide from the openings 342 and322 to the apertures 395 and 396 as discussed in FIGS. 4C-4F to releasethe posts 250 from the latching subsystem 300. As the posts 250 arereleased, the spring 244 of the coupling subsystem 240 deforms from afirst state at a length of d1 (e.g., FIG. 5A) to a second state at alength of d2 (e.g., FIG. 5B), where d2 is greater than d1, such that thecoupling subsystem 240 automatically detaches from the latchingsubsystem 300.

For example, when the posts 250 slide into the apertures 395 and 396,the spring 244 automatically releases from a compressed state at thelength d1 to a greater length d2. Simultaneously, the base 242 movesalong X dimension away from the spacer 246, thereby removing the posts250 away from the latching system 300 to decouple the coupling subsystem240 from the latching subsystem 300. The length d2 can be a naturallength (i.e., unstretched and uncompressed) of the spring 244, or alength longer than the compressed length d1 and shorter than the naturallength of the spring 244.

Reversibly, the coupling subsystem 240 can couple to the latchingsubsystem 300 by pressing the tips of the posts 250 into the openings342 and 322 of the latches 340 and 320. The openings 342 and 322 arewidened to accommodate the tips of the posts 250 until the concave edges351 and 331 latch to the grooves 256 of the posts 250. During thiscoupling process, the spring 244 is compressed from the length d2 to thelength d1, and the base 242 gets in contact with the spacer 246.

In some embodiments, the coupling subsystem 240 and the latchingsubsystem 300 comprise suitable electrical connection mechanism(s) toprovide power management and/or signal transmission between the speaker210 and the head-mounted display 110. For example, after the posts 250are inserted and latched to the openings 342 and 322 of the latches 340and 320, the tips 254 of the posts 250 may contact the base 360 andtransmit electric signals from/to the base 360. The base 360 is furtherelectrically connected to the strap 120 (e.g., the rigid segment 150) ofthe head-mounted display system 100.

In some embodiments, the one or more components of the latchingsubsystem 300 are made of materials such as stainless steel, acetalcopolymer, other polymers and other metals.

Combined with the coupling subsystem 240, the latching subsystem 300 canbe used for attaching the speaker 210 to the strap 120, and detachingthe speaker 210 from the strap 120 of the head-mounted display 110. Thelatching subsystem 300 and the coupling subsystem 240 enable the speaker210 to be removed from the user's ear without taking off the strap 120and head-mounted display 110.

In some embodiments, the audio subsystem 200 offers multiple degrees offreedom to adjust the position of the speaker 210 to fit differentusers. The adjustments with multiple degrees of freedom include, but arenot limited to, pivoting inward and outward relative to the user's ear,rotating within a vertical plane, and sliding upward and downward toadjust the height of the speaker 210. Various embodiments of themultiple degrees of freedom and related structures are described in U.S.patent application Ser. No. 14/627,639.

The foregoing description, for purpose of explanation, has beendescribed with reference to specific embodiments. However, theillustrative discussions above are not intended to be exhaustive or tolimit the scope of the claims to the precise forms disclosed. Manymodifications and variations are possible in view of the aboveteachings. The embodiments were chosen in order to best explain theprinciples underlying the claims and their practical applications, tothereby enable others skilled in the art to best use the embodimentswith various modifications as are suited to the particular usescontemplated.

What is claimed is:
 1. A strap system for a head-mounted display, thestrap system comprising: a rigid segment, having opposite first andsecond sides, to couple to the head-mounted display from the first side;and a latching subsystem coupled to the second side of the rigidsegment, the latching subsystem comprising: a plate including a pair ofslots to respectively receive a pair of posts protruding from adetachable audio system; and a pair of latches to latch to grooves inthe pair of posts, each latch of the pair of latches including anopening that overlaps a respective slot of the pair of slots, theopening to receive a respective post of the pair of posts.
 2. The strapsystem of claim 1, wherein each latch of the pair of latches comprises:a pair of members joined at a first end and unconnected at a second end,to define the opening; and a serpentine spring coupled to the first endof the pair of members.
 3. The strap system of claim 2, wherein theopenings are configured to widen to release the pair of posts to detachthe detachable audio system from the strap system.
 4. The strap systemof claim 2, wherein: each member of the pair of members includes aconcave edge portion facing the other member of the pair of members; andthe concave edge portions of the pair of members define the opening. 5.The strap system of claim 4, wherein the pair of latches are coupled tothe plate such that the serpentine springs overlap each other.
 6. Thestrap system of claim 5, wherein: each latch of the pair of latchescomprises a first portion coupled between the first end of the membersand a first end of the serpentine spring and having a first aperture;the plate comprises a protrusion corresponding to the first aperture ofboth latches of the pair of latches; and the protrusion of the plateextends through the first aperture of each latch of the pair of latchesto couple the plate to the pair of latches.
 7. The strap system of claim6, further comprising an elongated base, wherein the plate and the pairof latches are coupled to the elongated base over a first surface of theelongated base, and the rigid segment is coupled to the elongated baseover a second surface of the elongated base opposite to the firstsurface.
 8. The strap system of claim 7, further comprising an elongatedcover, coupled to the elongated base and the pair of latches, to coverthe serpentine springs.
 9. The strap system of claim 8, furthercomprising a spacer located between the elongated cover and the pair oflatches.
 10. The strap system of claim 8, wherein: the elongated coverincludes a pair of projections opposite to each other, each projectionhaving an aperture; each latch of the pair of latches further comprisesa second portion coupled to a second end of the serpentine springopposite to the first end of the serpentine spring, the second portionof the latch having a second aperture; the elongated base includes apair of apertures; and a pair of connectors couple the elongated cover,the pair of latches, and the elongated base through the apertures of thepair of projections, the pair of apertures of the elongated base, andthe second apertures.
 11. The strap system of claim 5, wherein, for eachlatch of the pair of latches: the opening narrows at a neck that formsan end of the concave edge portions; and the neck widens again to anaperture with a width equal to or greater than a diameter of the posts.12. A head-mounted display system comprising: a head-mounted display; astrap system for mounting the head-mounted display on the user's head,the strap system comprising: a semi-rigid segment to conform to aportion of the user's head; a rigid segment connected to the semi-rigidsegment and including a first side to couple to the head-mounted displayand a second side opposite to the first side; and a latching subsystemcoupled to the second side of the rigid segment; and a detachable audiosubsystem including a speaker and a coupling subsystem including a pairof posts to couple to the latching subsystem, each post of the pair ofposts having a groove, wherein the latching subsystem comprises: a plateincluding a pair of slots to respectively receive the pair of posts; anda pair of latches to latch to the grooves in the pair of posts, eachlatch of the pair of latches including an opening that overlaps arespective slot of the pair of slots, the opening to receive arespective post of the pair of posts.
 13. The head-mounted displaysystem of claim 12, wherein each latch of the pair of latches comprises:a pair of members joined at a first end and unconnected at a second end,to define the opening; and a serpentine spring coupled to the first endof the pair of members.
 14. The head-mounted display system of claim 13,wherein the pair of latches are coupled to the plate such that theserpentine springs overlap each other.
 15. The head-mounted displaysystem of claim 14, wherein: each latch of the pair of latches comprisesa first portion coupled between the first end of the members and a firstend of the serpentine spring and having a first aperture; the platecomprises a protrusion corresponding to the first aperture of bothlatches of the pair of latches; and the protrusion of the plate extendsthrough the first aperture of each latch of the pair of latches tocouple the plate to the pair of latches
 16. The head-mounted displaysystem of claim 13, wherein: each member of the pair of members includesa concave edge portion facing the other member of the pair of members;the concave edge portions of the pair of members define the opening; andthe openings are configured to widen to release the pair of posts todetach the detachable audio system from the strap system.
 17. Thehead-mounted display system of claim 16, for each latch of the pair ofthe latches, wherein: the opening narrow at a neck that forms the end ofthe concave edge portions; and the neck widens again to an aperture witha width equal to or greater than a diameter of the posts.
 18. Thehead-mounted display system of claim 12, wherein the detachable audiosubsystem further comprises: an arm coupled to the speaker; and a strapconnector including a first side coupled to the arm and a second sideopposite to the first side, wherein the coupling subsystem is coupled tothe second side of the strap connector, the coupling subsystemcomprising: a base including a first side engaged with the second sideof the strap connector and a second side opposite to the first side, thepair of posts extending from the second side of the base to insert intothe pair of latches; and a spring, contacting the second side of thebase, to detach the detachable audio system from the latching subsystemwhen the pair of posts decouple from the pair of latches.
 19. Thehead-mounted display system of claim 18, wherein each post of the pairof posts comprises: a first end inserted into a respective opening of aplurality of openings in the base, and a second end to couple to thelatching subsystem, the second end comprising: a tip to be inserted intothe opening of the latch; and the groove.
 20. A latching system forcoupling an audio system to a head-mounted display, the latching systemcomprising: a plate including a pair of slots to respectively receive apair of posts protruding from the audio system; and a pair of latches tolatch to grooves in the pair of posts, each latch of the pair of latchesincluding an opening that overlaps a respective slot of the pair ofslots, the opening to receive a respective post of the pair of posts,wherein each latch of the pair of latches includes: a pair of membersjoined at a first end and unconnected at a second end, to define theopening; and a serpentine spring coupled to the first end of the pair ofmembers.